Use 1% or 10% to estimate 8% of 310.

To estimate the 8% of 310, we use 10% method since 8 when rounded off is equals to 10.

The 10% of a number can simply be obtained by moving the decimal place one point to the left.

Therefore using the 10% method, the 8% of 310 is approximately 31.0

10% = 31.0

30 people weigh 160 pounds or more